Spark timing control



Dec. 22, 1964 B. WALKER SPARK TIMING CONTROL Filed July 20, 1962 27 INVENTOR.

United States Patent Ofiice 3,162,184 Patented Dec. 22, 1964 3,162,184 SPARK TlMiNG CONTROL Brooks Walker, 1280 (Zolumbus Ave, San Francisco, Caiif. Filed July 20, 1962, Ser. No. 211,449 3 (llaims. (Cl. 123-417) This invention pertains to a device to retard the spark every time the throttle is closed whether the motor is idling or being driven as when decelerating.

Other devices, such as US. Patent No. 2,988,074, issued June 13, 1961, to W. A. Lobdel et a1., shows a device to retard the spark when the suction in the manifold is higher than idle suction to retard the spark during deceleration but not at idle.

Applicants device retards the spark much more than normal whenever the throttle is in the closed position a when idling or when decelerating.

Another object is to obtain this retard by rotating the plate that carries the breaker points rather than retarding the entire distributor cap and wires though this control mechanism could be used to retard the entire distributor cap and assembly by a construction similar to that shown in said Lobdel et al., patent but by the control of its operating suction by the means shown in this invention rather than by the structure shown in said Lobdel et al. patent where retard is obtained during deceleration only.

Another feature of this invent-ion is the simple valve to control the retard powering vacuum which valve is actuated to effect the retard when the valve is closed or very nearly closed.

Another object is to provide a porting in the carburetor near the butterfly throttle valve that is open to the high suction at closed throttle operation only when the throttle is closed or almost closed and open to the space above the, butterfly or on the venting side of the throttle butterfly on cruise or acceleration positions of the throttle butterfly to thereby make a separate valve to control the suction which would thereby eliminate the need for the ex ra valve.

Previously for carburetor spark control carburetor ports have been provided through the venturi and just above the butterfly in its closed position on the high edge of the butterfly in a down draft carburetor so no high suction is available through said ports at closed throttle or idle throttle position and higher suction is obtained as the throttle is opened and again the suction aavilab-le is lower as the throttle is fully opened. Such characteristics are used to control the normal carburetor vacuum spark advance. This gives no suction controlled spark advance at idle, a considerable advance at cruise suction, and again very little (except governor spark advance) at full throttle.

I have illustrated my invention in the accompanying drawing, in which:

FIG. 1 is a side elevation partly cut away of a carburetor and a portion of an ignition system showing one form of my invention.

FIG. 2 is a side elevation of a portion of a carburetor partly cut away and showing another form of my invention.

In all figures like numerals of reference refer to corresponding parts.

In FIG. 1 I have shown a carburetor supplied with fuel through line 11. Butterfly control shaft 13 carries control arm 14 .and butterfly 18 which acts as a throttle valve. Choke shaft 12 controls the choke butterfly in the usual manner.

Carburetor 10 is attached to intake manifold 21 in any suitable manner. Throttle closed valve 25 is located so that stem 30 abuts against adjustable stop 16 which stops is secured to throttle control rod 21) by screw 17. Swivel is secured to throttle shaft by screw 1511 or other suitable means. Swivel 15 is pivotally attached to arm 14a of throttle control arm 14.

Stem of valve 25 is secured to valve pistons 31 and 32. Valve 25 has port 23 connected at all times to the intake manifold 21 by tube 22. Port 26 is connected to auxiliary spark control device by tube 27. Spark control device 4-0 carries diaphragm 31, rear housing 33, and support bracket 33b.

Control rod 34 is secured to diaphragm 31 by washers 32, shoulder 34b and nut 340. The end 34a is pivoted to breaker point plate 41 and secured by cotter pin 35.

Normal carburetor spark advance control device 50 is supplied carburetor controlled suction by pipe 49 which 1 may be connected to passage 60 leading to the carburetor venturi passage 60a, and to passage 61 leading to a location just above the high edge or" the throttle butterfly 18 in the throttle closed (or idle) position. See paragraph 4156, page 360, Glens Auto Repair Manual 1962 Edition.

Normal carburetor spark control device has diaphragm 55a urged to its upper position as shown in FIG. 1 by spring 52 when idling, as controlled by the carburetor vacuum through line as. Control rod 53 is secured to diaphragm 50a in the usual manner and carries upturned end 53a which rides in slot 41a which allows the extra retard as much as 10 after top center when actuated by mechanism 4-0 when the engine is idling or decelerating. With the throttle in the idle position and valve 25 in the position shown in FIG. 1, the spark will be retarded for idle and deceleration. Spring 55 returns breaker point plate 41 to the other end of slot 41a when the throttle is opened or not in idle position as the suction. from manifold 21 is shut off from tube 27 and diaphragm 31 when pistons 31 and 32 move to the left to connect line 27 to vent 24 and shuts off manifold vacuum port 23. This gives normal spark advance for all cruises and accelerating by normal carburetor spark advance device 50 and the centrifugal governor advance not shown; but gives extra retard on decelcrations and idle to give better burning of the fuel and less smog during these conditions as well as less brake fight on decelerations. Shaft 43 carries the breaker cam and distributor arm in the usual manner as shown in said Glens New Auto Repair Manual. 1962 Edition.

in FIG. 2 I have shown an alternate control for the vacuum to control auxiliary spark control device 30. Here we show an anti-smog type carburetor operating at idle with a closed throttle butterfly 51 which is carried on carburetor throttle shaft 511. Idle fuel comes down passage 52 from the float bowl with the usual air bleeds if necessary to solenoid idle valve 53 which controls idle needle 53a in any suitable manner as in Hall US. Patent No. 2,809,623, issued October 15, 1957.

Fuel free air is admitted below the butterfly fairly tangentially through tube 58 past adjustment screw 56 into nozzle 57 which is fairly tangential to the bore below the butterfly 51 for better mixing of the idle fuel and fuel free air for idle mixture control.

Port 53 is connected to port 59a leading just below the lower edge of the low side of butterfly 51 in down draft carburetor 9. Port 59 and passage 59a are con nected to line 27 which connects to auxiliary spark control 40 and replaces valve 25 shown in FIG. 1.

In operation at idle or deceleration with throttle 51 in the position shown, port 5% will be subjected to full manifold vacuum and the spark will be retarded by device 4!) rotating breaker plate 41 to the position shown in FIG. 1. As the throttle is moved to a partial or fully open position for cruise and acceleration the lower end of butterfly throttle valve 51 will move past port 59a and change the suction in port 59 from manifold suction to the suction existing above the butterfly 51 which is very slight. In this position spring 55 will move breaker plate 41 so that normal carburetor spark advance rod 3 7 end- 53a is held against the upper end of slot 41a of breaker plate 41, as viewed-in FIG. 1, except at closed throttle (or idle throttle) positions of engine operation. 'This .portingof; thev suction to "controlv special retard device 40, eliminates the necessity for valve 25. and may be cheaperand satisfactory for some installations.

In case a: carburetor is used in which idle takes, place with a crackedthrottle, it may be necessary to move port 59a just below the lower edgeof the butterfly when in this idle position rather than below the lower edge of the butterfly in! the fully closed, throttle position.

I have illustrated my invention in these various forms; however many other variations may be possible within the scope of this invention.

Tothose skilled in the art to which this invention relates many changes in construction and Widely differing embodiments and applications of the invention will suggest themselves without departing from the spirit and scope of the invention. The disclosures and description herein are purely illustrative and are not intended to be in anyv sense limiting.

I claim as my invention: 1. An engine including in combination: a carburetor having a main air passage therethrough, a throttle valve in said air passage, a first, port to said .air passage on the intake side of said valve whenv said valve is in its engine-idle position, and a second port to said air passage on the engine side of said valve when said valve is in its engine-idle posit-ion, an ignition distributor having a housing and a breaker pl ate rotatable relative to said housing,

engine-lsuction openated spark advance mechanism connected to said firstport and to said breaker plate for rotation of said breaker plate in the spark-advance direction under the action of suction fromsaid first and for providing dilferent vacuum operated advances 4 of said breaker plate for eachsubstantial incremental change in suction from said first port, an engine-suotion-openated. spark-retard mechanism connected to said second; port and to said breaker plate forjrotatio-n of said plate in the'spark-retard direch'on, second spring means much less resistive-than said first spring means for opposing the rotation of said breaker plate in the spark-retard direction, and control means actuated upon: movement of said throttle valve to its 'en-ginea'dle position for admitting high engine suction; tosaid spark-retard mechanism. 2. The engine of claim 1 havinga throttle operating means connected to said thrlottle valve for actwationthereof, said control means including a conduit between said second port and said s park-retardmechamism and a control valve in said conduit. for blocking and opening said conduit, and means actuated by said throttle openating means for" opening said control valve when. said throttle openating means moves said throttle valveto its engineridle position. 1

3. The engine of claim 2 in which said control valve is cl osedby said throttle operating means except during engine idle position so that said spark retard mechanism offers no substantial opposition to said spark advance mechanism when said spark advance, mechanism is operative when said'engine isoperatinguncler substantial loads.

ReferencesCited in the file of this patent UNITED STATES PATENTS 1,962,931 Mallory June 12, 1934 2,087,339 Anthur July 20, 1937 2,383,898 Udale Aug. 28', 1945 2,544,608. Mallory Mar. 6, 1951 3,027,884 Bale et a1. Apr. 3, 1962 i, FOREIGN PATENTS 514,206 m Fr'ance Nov. 13, 1920 616,940 1 Germany Aug. 8, 1935. 

1. AN ENGINE INCLUDING IN COMBINATION: A CARBURETOR HAVING A MAIN AIR PASSAGE THERETHROUGH, A THROTTLE VALVE IN SAID AIR PASSAGE, A FIRST PORT TO SAID AIR PASSAGE ON THE INTAKE SIDE OF SAID VALVE WHEN SAID VALVE IS IN ITS ENGINE-IDLE POSITION, AND A SECOND PORT TO SAID AIR PASSAGE ON THE ENGINE SIDE OF SAID VALVE WHEN SAID VALVE IS IN ITS ENGINE-IDLE POSITION, AN IGNITION DISTRIBUTOR HAVING A HOUSING AND A BREAKER PLATE ROTATABLE RELATIVE TO SAID HOUSING, AN ENGINE-SUCTION-OPERATED SPARK-ADVANCE MECHANISM CONNECTED TO SAID FIRST PORT AND TO SAID BREAKER PLATE FOR ROTATION OF SAID BREAKER PLATE IN THE SPARK-ADVANCE DIRECTION UNDER THE ACTION OF SUCTION FROM SAID FIRST PORT, FIRST SPRING MEANS FOR OPPOSING THE ROTATION OF SAID BREAKER PLATE IN THE SPARK-ADVANCE DIRECTION AND FOR PROVIDING DIFFERENT VACUUM OPERATED ADVANCES OF SAID BREAKER PLATE FOR EACH SUBSTANTIAL INCREMENTAL CHANGE IN SUCTION FROM SAID FIRST PORT, AN ENGINE-SUCTION-OPERATED SPARK-RETARD MECHANISM CONNECTED TO SAID SECOND PORT AND TO SAID BREAKER PLATE FOR ROTATION OF SAID PLATE IN THE SPARK-RETARD DIRECTION, 